The investment cycle of private equity investment fund is very long, so its source of funds is mainly long-term investors. Generally speaking, private equity investment funds will be funded by institutional investors in their main investment fields. The way of raising private equity investment funds is different from ordinary funds, and usually adopts the way of investment commitment. When a fund management company is established, it does not necessarily require all partners to invest a predetermined amount of capital, but requires investors to make commitments. When managers find suitable investment opportunities, they only need to inform investors a certain amount of time in advance. There are certain risks. If investors fail to invest in time, they will be fined as agreed. Therefore, the amount of capital raised by the Fund is only the promised amount of capital, not the actual amount of investment or the amount of funds held. In actual fundraising activities, the fund has a certain fundraising period. When the deadline expires, the Foundation announces the subscription deadline. The same fund can have multiple subscription deadlines, but generally not more than three times. In practice, the fund can hire an institution to raise funds.